pci_size() had a check that made it return 0 (i.e. an error) in some cases. It took me a while to work out in which situations exactly this check triggered: If writing 0xfffffffe to the BAR register doesn't change it's value and the masked value isn't in the form 0b1....10...0. This patch replaces the check in pci_size() by a similar check in setup_device() where it is more expected to happen. This allows to simplify pci_size() considerably. The new check is a bit more strict as it doesn't consider the value the BAR register holds initially and bails out iff the maximal base value isn't in the expected format. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx> --- drivers/pci/pci.c | 30 ++++++++++++++---------------- 1 file changed, 14 insertions(+), 16 deletions(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 837e17aa8397..72689560d598 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -144,18 +144,10 @@ static struct pci_dev *alloc_pci_dev(void) return dev; } -static u32 pci_size(u32 base, u32 maxbase, u32 mask) +static u32 pci_size(u32 maxbase) { - u32 size = maxbase & mask; - if (!size) - return 0; - - size = (size & ~(size-1)) - 1; - - if (base == maxbase && ((base | size) & mask) != mask) - return 0; - - return size + 1; + /* isolate right-most set bit */ + return maxbase & ~(maxbase - 1); } @@ -169,7 +161,7 @@ static void setup_device(struct pci_dev *dev, int max_bar) cmd & ~(PCI_COMMAND_IO | PCI_COMMAND_MEMORY)); for (bar = 0; bar < max_bar; bar++) { - u32 orig, barval, size, mask; + u32 orig, barval, maxbase, size, mask; const char *type; int restype; unsigned long resflags; @@ -206,13 +198,19 @@ static void setup_device(struct pci_dev *dev, int max_bar) last = &last_mem; } - size = pci_size(orig, barval, mask); - if (!size) { - pr_debug(" pbar%d: bad %s size (orig=%08x, barval=%08x, type=%s)\n", - bar, type, orig, barval, type); + maxbase = barval & mask; + + /* + * if maxbase isn't in the form 0b1...10...0 there is something + * fishy + */ + if ((maxbase | (maxbase - 1)) != (u32)-1 || maxbase == 0) { + pr_debug(" pbar%d: !! barval=%08x maxbase=0x%08x\n", bar, barval, maxbase); continue; } + size = pci_size(maxbase); + if (ALIGN(*last, size) + size > dev->bus->resource[restype]->end) { pr_debug(" pbar%d: !! type=%s allocbase=0x%08x + size=0x%08x > resource_end=%pa (barval=%08x)\n", bar, type, ALIGN(*last, size), size, &dev->bus->resource[restype]->end, barval); -- 2.16.3 _______________________________________________ barebox mailing list barebox@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/barebox